The ClamAV engine should have a similar detection rate as any other, but is known to respond more quickly to new outbreaks - a new reported virus can get added to the database and deployed within one hour. As we build only the CGP helper but are not involved in the engine code, we don't directly perform comparative tests. However, ClamAV is normally included when a publication decides to do such a test, so you should be able to find recent comparative information.
No. It's a fact that 99.9+% of nowaday viruses are sent by automated bots and the message payload is not of any interest for the user, and it's in our opinion that the end user is happier not knowing about the scale of attacks, so we did not add such report generation. After all, receiving 10-15 virus warning mails a day is as useless as receiving spam. Anyway, we also recommend, whenever possible, to run the AV filter in synchroneous mode in CGP so CGP rejects the infected messages during the SMTP session (no bounce, no discard, just reject). This way, a legitimate sender would immediately be notified about the issue. No mail lost. See also A Good Antispam and Antivirus Setup.
CGP-ClamAV will do parallel (threaded) scanning, up to the number of CGP Enqueuer processors, if you start it with the -mt flag on the command line.
Yes, you can. This increases security at the price of more processing. We would recommend that you run CGP-ClamAV first, then the other AV product, and monitor viruses caught by the other AV product but not by the ClamAV engine. You will probably find out after a while that you are likely paying too much for the other product.
Your server is not at risk. We don't sell licenses of CGP-ClamAV, neither we sell licenses of the ClamAV engine. What we sell is a 1-year download right for a package containing a compiled and slightly-modified version of the ClamAV engine, embedded in helper code made to run correctly in CGP. As long as your download right is valid, you can download new releases of the package.
When your download right expires, the versions you already have downloaded are still valid, still works, and will continue to automatically download virus signatures from ClamAV servers, which are not under out control.
The only ways your version of CGP-ClamAV could fail is if there is a bug discovered later, or if the ClamAV database or db distribution method change enough.
However, keeping your CGP-ClamAV version up to date ensures you you have the latest version of the engine, the most bug-free version, the most optimized one, and you get new features when they are released.
For all of these reasons, we do not send renewal notifications, as upgrading the filter is a manual action anyway. When you choose to upgrade it and discover your download right is expired, it's time to renew it. You don't have to actually renew it each and every year.
You can subscribe to release news at https://www.clamav.net, when a new engine version is released it's likely a new version of the filter will be released within a few days.
The ClamAV engine in CGP-ClamAV is Free software, so is the helper using it. We respect the OpenSource license (GPL 2) by making the filter sources available to anyone purchased it.
Due to technical restrictions, the sources are available for download only to the people for which the binary download right is still valid - when you purchase a license, the filter binaries and sources are available for download for a year.
As the GPL specifies the sources should be available for three years, if your download right is expired and you want to obtain the sources of the latest version you downloaded, please contact us and we will make them available to you within reasonable time.